An arrest in the lower Hudson Valley led to the largest seizure in the US of a drug deadlier than fentanyl.

On Wednesday, the Clarkstown Detective Bureau announced the results of a joint law enforcement operation with the New York City Police Department in the month of September that netted over 15 kilograms of controlled substances and the arrest of a 47-year-old Massachusetts man.

The Clarkstown Police Street Crime Unit worked in conjunction with the NYPD Intel Unit and Queens Major Case Squad on a large scale narcotics trafficking investigation.

Acting on credible information the street crime officers conducted a traffic stop of a tractor-trailer in West Nyack. Upon stopping the tractor-trailer, officers were assisted by a Clarkstown police K-9 unit to search the truck.

Officers allegedly found one kilogram of fentanyl, one kilogram of heroin, 13 kilograms of cocaine and 1,551 imitation Oxycodone pills containing Fentanyl.

The 35 pounds of illegal narcotics which were seized have an estimated street value of $2.4 million, police say. Fentanyl is 100 times more powerful than morphine and in its unadulterated form, one kilogram has the potential to fatally overdose 500,000 individuals, according to authorities.

The driver of the truck, Alexis Victorero, 47, of Milford, MA was charged criminal possession of a controlled substance, a felony. He was later indicted by a Rockland County Grand Jury for four counts of criminal possession of a controlled substance 1st, felonies.

Victorero was among 11 charged following a long-term investigation that led to 11 arrests of alleged drug traffickers and the largest seizure in the country of a substance deadlier than fentanyl, according to the Queens County District Attorney's Office.

More From WZAD-WCZX The Wolf